The general objective of the proposed continuation of the present program is to provide comprehensive improvements in ophthalmic diagnosis and in monitoring treatment. These improvements will permit optimal selection and tailoring of therapeutic methods. The proposed studies will continue to develop and apply advanced ultrasonic tissue characterization techniques derived from ultrasonic spectrum analysis and related signal processing methods such as cepstrum analysis and deconvolution. A major thrusts of the program will be to improve the specificity of diagnosis based on acoustic signatures that incorporate sets of several ultrasonic parameters. These methods will continue to be implemented, tested, and assessed for reliability and refined in a working clinical setting. The methods will be applied to detecting, identifying and grading a wide variety of ocular and orbital diseases. A database of tissue characterization parameters has been established; it emphasizes intraocular tumors, particularly melanomas and metastatic carcinomas. This computer library will continue to be expanded and serve the basis of efforts to identify sets of parameters capable of reliably characterizing specific diseases, and in some cases specific forms of a given disease (e.g. spindle melanoma compared to mixed/epithelioid melanoma). On-line clinical processing of scan data will continue to be used to evolve improved examination techniques, analytic procedures, and diagnostic protocols. This will lead to optimal application of the developed methodologies, particularly recognition of tissue signatures and therefore efficacious interpretation of scan data in support of diagnostic and treatment decisions. The proposed continuation of this program will utilize the collaborative relationship between engineering and clinical staff that has been in effect since the inception of these studies. Engineering aspects of the project will continue to be undertaken by the personnel of Riverside Research Institute; clinical studies will be performed by the members of the staff of the Department of Ophthalmology at Cornell University Medical College.